Jet deflecting device

ABSTRACT

This invention relates to a jet deflecting device, particularly adapted for deflecting the propellent gas jet of an aircraft jet engine, which comprises pivot bearing means connecting the jet discharge nozzle with a stationary part of the jet engine, and extensible tubular means connected between said nozzle and said stationary part, said tubular means being variable in curvature in correspondence with the nozzle pivoting movement and having a transitional jet guiding surface between said nozzle and said stationary part.

United States Patent 1 Buchstaller Nov. 20, 1973 [5 4] JET DEFLECTINGDEVICE [75] Inventor: Anton Buchstaller, Friedrichshafen,

Germany [73] Assignee: Dornier A.G.,

Friedrichshafen/Bodensee, Germany 22 Filed: Oct. 27, 1971 211 Appl.No.:193,094

[30] Foreign Application Priority Data Dec. 23, 1970 Germany P 20 63342.5

[52] US. Cl 244/56, 244/12 A, 244/23 A, 239/265.35

[51] Int. Cl B64d 27/18 [58] Field of Search 244/53 R, 54, 55, 244/56,23 A, 23 D, 12 A, 12 D; 239/265.11,

[56] References Cited UNITED STATES PATENTS 3,380,660 4/1968 Markowski239/265.19

3,184,917 5/1965 Coovette et a1. 239/265.35 X 3,178,887 4/1965 Wilde eta1. 244/23 D 3,259,405 7/1966 Heller.... 138/121 X 2,608,820 9/1952Berliner.... 138/121 X 2,891,740 6/1959 CampbelL. 244/12 D 3,003,31210/1961 Jewell 239/265.35 3,266,244 8/1966 Schulze et al. 239/265.353,290,887 12/1966 Poole 239/265.35

Primary ExaminerGeorge E. A. Halvosa Assistant Examiner-E. R. KazenskeAttorneyJames E. Bryan 5 7 ABSTRACT This invention relates to a jetdeflecting device, particularly adapted for deflecting the propellentgas jet of an aircraft jet engine, which comprises pivot bearing meansconnecting the jet discharge nozzle with a stationary part of the jetengine, and extensible tubular means connected between said nozzle andsaid stationary part, said tubular means being variable in curvature incorrespondence with the nozzle pivoting movement and having atransitional jet guiding surface between said nozzle and said stationarypart.

6 Claims, 7 Drawing Figures PAIENTEI] #0! '2 0 191 5 SHEET 1 k w k w miINVENTOR ANTON BUCHSTALLER ATTORNEY PATENIEDnuvzo 197a F/GZ I INVENTORANTON BUCHSTALLER AT ORN'EY JET DEFLECTING DEVICE The present inventionrelates to a jet deflecting device or system, designed particularly fordeflecting the propellent gas jets of jet engines in aircraft, whereinthe jet discharge nozzle is mounted by way of pivot bearing supports atthe stationary jet guiding part of the propulsion unit.

In certain airplane configurations it is required that the propellentgas jets of propulsion engines be deflected from the discharge directionthereof in the direction toward the slotted flaps at the trailing wingedge in order that the short take-off and landing properties beimproved. It is possible to achieve therewith both a jet componentfurnishing lift, and an increase of the lifting power aerodynamicallyduring slow flight, i.e. during take-off and landing.

In aircraft having vertical flight properties with the aid of jet liftengines, it is customary to deflect the propellent gas jet dischargingfrom the jet lift engines by a specific angular value from thedischarging direction and to thereby produce braking thrust. It is knownto arrange for this purpose deflector vanes in the area of the dischargenozzle, these vanes being so mounted as to be adapted to be pivoted intothe propellent gas jet.

Another prior art arrangement provides for a flexible jet discharge tubeconsisting of a eries of movable rings which are conically tapered andwhich partially overlap each other. The manufacture of such flexibletube parts is complicated, and furthermore the problem of sealing isdifficult. This known arrangement results in a considerable elongationof the entire propulsion unit design, which fact becomes noticeableunfavorably, particularly with the use thereof in lift engines. Inaddition thereto, significant resistances to flow are produced in theafore-mentioned flexible tube parts as the transi tions between theadjacent ring parts.

The present invention provides a jet deflecting device or system whichassures in all deflecting positions a constant guide of the discharginggas jet and a flawless sealing of the jet guide, while the flowresistances are kept as small as possible.

This is attained, in accordance with the present invention, by virtue ofthe fact that connected with the jet outlet or discharge nozzle and thestationary jet guide is a tube part which is adapted to be varied in thecurvature thereof according to the degree of the nozzle pivoting andwhich has a transitional jet guiding surface from the jet guidingsurface of the stationary jet guide and the inner propulsion unit cowlor sheathing, to the jet guiding surface of the jet nozzle.

A jet deflecting device designed and constructed in this manner isextremely simple in the construction thereof. Achieved furthermore is afaultless constant jet guide or guidance in all of the deflectingpositions and also in the neutral position, i.e. in the position inwhich no deflection takes place. In all of the positions of the nozzle,any impairment of the discharging propellent gas jet by means ofprojections extending into the flow or any recesses interrupting the jetguiding surface are largely eliminated. The tubular part which isinserted within the stationary jet guide and the jet discharge nozzleserves therein only for forming a transitional jet guiding surface. Thebearing support of the pivotal jet discharge nozzle is arranged directlyat the stationary jet guiding part.

A further embodiment of the present invention proposes that the tubularpart be constructed in a manner known per se like an undulated andfolded tubular portion. This assures particularly also in the neutralposition of the jet discharge nozzle, i.e. when the propellent gas jetof the propulsion unit is not intended to be deflected, an almostgap-free transition of the outer contour of the stationary jet guide tothe outer contour of the jet discharge nozzle. This construction avoidsan increase of the aerodynamic drag, as well as a disturbance of thebypass flow when a bypass type engine is used. The result is an outercontour being closed toward the outside in any position of the jetdischarge nozzle, while the internally positioned folding and,undulating tubular part allows for a constant guide of the propellentgas jet independently of the position of the pivotal jet dischargenozzle.

In order to be able to achieve a guide of the propellent gas jet withinthe folding and/or corrugated tubular part which is as low in resistanceas possible, the annular gaps formed by reason of the profiling of thetubular part are positioned at the inner surface of the folding and/orcorrugated tubular part as annular plates overlapping in any position ofthe jet discharge nozzle. The annular plates thus form the transitionaljet guiding surface which adapts in its curvature to the respectivedeflecting position of the jet discharge nozzle and brings about aconstant guide to the propellent gas jet from the stationary jet guidingportion to the jet discharge nozzle.

One embodiment of the present invention is illustrated in theaccompanying drawings, wherein FIG. 1 is a general view of a jet enginemounted below a wing and in a side view thereof;

FIG. 2 illustrates, in a portion taken from FIG. I and shown at anenlarged scale, the pivot nozzle in the normal position and in alongitudinal cross-sectional view thereof;

FIG. 3 illustrates, in a portion taken from FIG. 1 and shown at anenlarged scale, the pivot nozzle in a pivoted position and in alongitudinal cross-sectional view thereof;

FIGS. 4 to 6 illustrate, in a portion taken from FIGS. 2 and 3,respectively, and shown at an enlarged scale, details of the pivotnozzle, and

FIG. 7 schematically illustrates a further design of the folding and/orcorrugated tubular part in a longitudinal cross-sectional view thereof.

The drawing shows the wing of an aircraft together with bypass typeengines being mounted on both sides of the airplane fuselage and securedbelow the wing by struts.

In FIG. 1, one of the bypass engines has been identified with referencenumeral 2 and the airplane wing has been designated with referencenumeral 3. The bypass engines 2 are mounted below the wing in the areaof the leading wing edge with the aid of the supporting struts 4.Mounted at the trailing edge of the wing 3 and the double slotted flaps6 and 7, respectively, which are utilized for purposes of increasing thelift during take-off and landing. Reference numeral 10 furtheridentifies the cowling forming the engine nacelles. Positioned withinthe front portion of the cowling 10 is the air inlet opening 11, andpositioned therebehind are the compressor vanes 12 of the single-stagelow-pressure compressor. The bypass flow channel 17 is formed by meansof the outer engine-or power unit cowling l4 and the inner engine orpower unit cowling 15. The air supply channel 9 which is positionedconcentrically with respect to the bypass flow channel 17 passes orguides a portion of the air furnished by the low pressure compressor tothe high pressure compressor and to the combustion chambers and, also,to the turbine from which the propellent gas jets are fed to the jetdischarge or outlet nozzle 20; the elements of the engine or power unitreferred to herein have not been illustrated.

As is apparent particularly from FIGS. 2 and 3, the jet discharge nozzle20 is herein mounted separately from the stationary jet guide formed bythe inner engine or power unit cowling 16. The jet discharge nozzle 20-engages over a part of its longitudinal extension in an annular recess24 in the area of the free end of the inner engine or power unit cowling16. The section of the jet discharge nozzle 20 which engages in therecess 24 has a peripheral area or surface 27 in the form of a sphericalsegment by means of which latter a pivoting movement of the nozzle 20within the recess 24 of the jet guide is rendered possible. An annularrecess 28 is machined into the jet guiding surface 32 extending to thejet discharge opening 26 (FIG. 1) of the nozzle 20. The jet dischargenozzle 20 further has forked portions 37 in which engage correspondingpivot bearing parts 35 at the inner engine cowling 16. The forkedportions 37 of the jet discharge nozzle 20 and the pivot bearing parts35 of the stationary jet guide 16 are hingedly connected with each otherby way of pivot bearing bolts 38 being coaxially arranged with respectto each other so that the jet discharge nozzle 20 is adapted to executea pivoting movement about the axes being positioned parallel to thetransverse airplane axis. Coupled to the pivot bolts 38 are rockinglevers 39 which are connected to a drive mechanism, not shown, by way ofa linkage system 40 on both sides of the inner engine cowling 16.Inserted within the annular recess 24 of the inner engine cowling l6 andthe annular recess 28 at the jet discharge nozzle 20 is a folding and/orcorrugated tubular part 45 which serves as hinge expansion compensatingmeans.

As is apparent from FIGS. 4 to 6 respectively, the tubular part 45consists in this construction of individual profiled elements 44 whichare composed in each case of an annular profiled section 46 having alyre-like cross-section, and adjacent cylindrical or cylinder-likesections 48 and/or 49. The cylinder-shaped section 48 of the profiledelements 44 overlaps in every pivoting position of the jet dischargenozzle 20 the cylindrical section 49 and the section 48 of the adjacentprofiled element 44, and covers at the same time also the annularopening which points toward the jet guide and is formed by the lyre-likeannular profiled section 46. Two adjacent profiled elements 44 each areconnected to each other with the cylindrical sections 48 and 49 thereofbyway of a connection 50, whicy may be made by spot-welding. Thecylindrical sections 48 have on a portion of the longitudinal extensionthereof a step 52 and the set-off portion has been designated withreference numeral 48. The cylindrical sections 48 are thus positioned onthe same diameter. Accordingly, the cylindrical sections 48, 48' of theprofiled elements 44 constitute a transitional jet guiding surface 33between the jet guiding surface 31 of the inner engine cowling l6 andthe jet guiding surface 32 of the jet discharge nozzle 20 (FIGS. 2 and3).

The operation of the construction described hereinabove according toFIGS. 1 to 6 is as follows If it is intended that a deflection of theprimary jet being guided through the jet discharge nozzle 20 be madefrom the outlet direction toward the rear in the direction toward thedouble slotted flaps 6 and 7, the jet discharge nozzle 20 is moved byway of the linkage system 40 and the rocking levers 39 about the pivotbearing bolts 38. At that time there takes place due to the connectionof the tubular part 45 on the one hand with the stationary jet guide 16and, on the other hand, with the jet discharge nozzle 20, acorresponding curvature of the tubular part 45, and the contraction inlength of the tubular part 45 above the pivot bearing bolts 38, and thelengthening thereof below the bolts 38 with respect to the normalposition will be absorbed by the lyre-like annular profiled sections 46.Thus there will be produced between two annular profiled elements each adistance variation x and/or x" as compared to the normal distance x. Dueto the fact that the cylindrical tube-shaped section 48, 48 of eachannular profiled element 44 overlaps the annular opening of thelyre-like annular profiled section 46 and the cylindershaped section 48of the adjacent annular profiled element 44, a transistional jet guidingsurface 33 is formed through which the propellent gas jet is constantlyguided, even in the pivoted position of the jet discharge nozzle 20, bythe stationary jet guide l6 to the jet nozzle 20. The adjustment oradaptation of the cylindershaped sections 48, 48' to the curvature ofthe annular profiled elements 44 is brought about by the unilateralconnection of these sections 48, 48' with the adjacent cylinder-likesection 49 of the annular profiled elements 44.

FIG. 7 illustrates a further embodiment of a folding and/or corrugatedtubular part 45. In this construction, the connection between thestationary jet guide 16 and the jet discharge nozzle 20 is establishedby way of a corrugated tube, made in one piece, having a lyre-likeannular profile section 53 and cylindrical sections 54 and/or 54'.Rigidly coupled to the section 54' of each lyre-like annular profilesection 53 via a connection 56 is a cylindrical part 55 which will ineach case overlap the annular opening of the lyre-like annular profilesection 53 and the adjacent cylindrical section 54 in any pivotedposition of the jet discharge nozzle 20. The cylindrical portion formstherein the transitional jet guiding surface 33 from the stationary jetguide 16 to the jet discharge nozzle 20.

It will be obvious to those skilled in the art that many modificationsmay be made within the scope of the present invention without departingfrom the spirit thereof, and the invention includes all suchmodifications.

What is claimed is:

l. A jet deflecting device, particularly adapted to defiect thepropellent gas jet of an aircraft engine, which comprises a jet nozzlepivotally mounted on' a stationary portion of a jet engine and having anouter surface, adjacent said jet engine, formed as a spherical segmentpositioned within a recess formed in the outer sheathing of said jetengine and said nozzle having a curvature and a sufficient length toform a substantially smooth outer contour from said jet engine in anypivotal position of said nozzle; a recess in said nozzle adjacent saidrecess and a corrugated section mounted within said recesses in said jetengine and said nozzle, having one end thereof attached to said jetengine and the other end thereof attached to said nozzle and theopenings of the ridges of said corrugated section facing inwardly; andcover means covering said openings and having a length sufficient toform a substantially smooth inner contour between said jet engine andsaid nozzle in any pivotal position of said nozzle.

2. A jet deflecting device according to claim 1 wherein the corrugatedsection has a constant degree of extension and contraction along itslength.

3. A jet deflecting device according to claim 1 wherein the ridges ofthe corrugated section are folded at the openings of said ridges to formridges of cylindrical cross-section.

4. A jet deflecting device according to claim 1 wherein the cover meansincludes a separate cover for each of the openings of the ridges of thecorrugated section which are formed as an integral part of the nextadjacent ridge of said corrugated section.

5. A jet deflecting device according to claim 4 wherein each cover isfixedly attached to the corrugated section adjacent one side of theopening of the ridge, is stepped inwardly and then extendslongitudinally at a constant diameter to a point beyond the other sideof said opening of said ridge.

6. A jet deflecting device according to claim 1 wherein the corrugatedsection is formed as a single piece and the cover means includes aseparately formed cover for each of the openings of the ridges of thecorrugated section and has one end thereof attached to the grooveportion connecting two of the ridges of the corrugated section andterminates at a point beyond the opening of one of said two ridges.

1. A jet deflecting device, particularly adapted to deflect thepropellent gas jet of an aircraft engine, which comprises a jet nozzlepivotally mounted on a stationary portion of a jet engine and having anouter surface, adjacent said jet engine, formed as a spherical segmentpositioned within a recess formed in the outer sheathing of said jetengine and said nozzle having a curvature and a sufficient length toform a substantially smooth outer contour from said jet engine in anypivotal position of said nozzle; a recess in said nozzle adjacent saidrecess and a corrugated section mounted within said recesses in said jetengine and said nozzle, having one end thereof attached to said jetengine and the other end thereof attached to said nozzle and theopenings of the ridges of said corrugated section facing inwardly; andcover means covering said openings and having a length sufficient toform a substantially smooth inner contour between said jet engine andsaid nozzle in any pivotal position of said nozzle.
 2. A jet deflectingdevice according to claim 1 wherein the corrugated section has aconstant degree of extension and contraction along its length.
 3. A jetdeflecting device according to claim 1 wherein the ridges of thecOrrugated section are folded at the openings of said ridges to formridges of cylindrical cross-section.
 4. A jet deflecting deviceaccording to claim 1 wherein the cover means includes a separate coverfor each of the openings of the ridges of the corrugated section whichare formed as an integral part of the next adjacent ridge of saidcorrugated section.
 5. A jet deflecting device according to claim 4wherein each cover is fixedly attached to the corrugated sectionadjacent one side of the opening of the ridge, is stepped inwardly andthen extends longitudinally at a constant diameter to a point beyond theother side of said opening of said ridge.
 6. A jet deflecting deviceaccording to claim 1 wherein the corrugated section is formed as asingle piece and the cover means includes a separately formed cover foreach of the openings of the ridges of the corrugated section and has oneend thereof attached to the groove portion connecting two of the ridgesof the corrugated section and terminates at a point beyond the openingof one of said two ridges.